Type 1: Custom assembly from off-the-shelf parts. In this model, the only unusual (but still off-the-shelf) parts are usually in the area of network acceleration (or occasionally encryption). Also, the box may be balanced differently than standard systems, in terms of compute power and/or reliability.

Type 2 (Virtual): We don’t need no stinkin’ custom hardware. In this model, the only “appliancy” features are in the areas of easy deployment, custom operating systems, and/or preconfigured hardware.

My recent flurry of research into computing appliances was spurred by a column I just submitted to Network World. In that column there’s a URL – pointing to this post – promising a guide to more details on that research. Thus, here’s a set of links to my posts of the past few months on computing appliances, both here and on DBMS2.

By way of contrast, there’s also a group whose stance is more along “hardware/schmardware” lines. Sendio and Proofpoint (in most cases) don’t really do anything special at all in their boxes; what’s more, Proofpoint actually has significant software-only deployments over VMware’s virtualization layer. Kognitio and Greenplum think their software-only data warehouse offerings are appliance-equivalents too; indeed, Greenplum’s software is sold mainly bundled with Sun hardware (to the extent it’s sold at all), and Kognitio is hinting at an appliance-like offering for competitive reasons as well. Check Point Software plays both sides of the field; it offers its own kind of “virtual appliance,” but also gets many of its sales through appliance vendors. Its most interesting such partner, if not its biggest, is Crossbeam Systems, which in my opinion may very well represent the future of appliance technology.

I talked with Proofpoint today, and got a more positive view about VMware’s virtual appliance strategy than I’ve gotten from other appliance vendors. They cite over 500 downloads in the past couple of months, of which a significant fraction have turned into actual sales. Specific deployment scenarios they mentioned include:

Demo (of course).

Tweak, test, deploy – between patches and new anti-spam rulesets, Proofpoint users seem to have a rapid change/test/deploy cycle. Virtualization makes it possible to do that without having multiple copies of an appliance.

Disaster recovery– this seems to be a big one.

“Surges” – depending on what the bad guys are doing, one’s need for anti-spam servers can go up and down in a hurry. Virtualization makes it easy to respond.

I chatted with VMware today about virtualization, virtual appliances, and so on. But first we covered some basics:

VMware quotes a figure of 20,000 enterprise customers, if you count everybody who is at least testing the software and so on; i.e., it’s a somewhat inflated figure. Still, the “real” number is surely big.

They claim ¼ of those have a “VMware first” policy, to deploy new apps on a virtual rather than dedicated machine. That’s impressive until you realize enterprise try to roll their own apps as rarely as possible these days.

They suggest VMware is extremely helpful at times you’d like to have two copies of the same platform – e.g., for development, or when you have to take the system down for brief maintenance. It’s hard to argue with that claim.